Best Study Materials for GIAC GASF Exam?

I am looking for the GIAC GASF exam and wanted to get some advice on the best resources to use. For those who have taken the exam or are preparing for it, I am curious to know what study materials you found most helpful.

I have seen Pass4Future GASF practice questions. Are they updated or accurate in terms of difficulty and style compared to the real exam? I am trying to gauge whether they are useful for preparation or if there are better practice tests out there.

Finally, how important is hands-on experience with forensic tools like Cellebrite or Oxygen? Should I focus more on practical experience, or can I get by with string theory?

Thanks in advance for any tips!